In case you forgot about the Harry Reid-Mitt Romney tax spat, here’s a recap.

In the summer of 2012, Reid said someone who worked with Bain Capital, which Romney led, called his office to say that Romney “didn’t pay any taxes for 10 years.”

“He didn’t pay taxes for 10 years! Now, do I know that that’s true? Well, I’m not certain,” Reid told the Huffington Post in an interview. “But obviously he can’t release those tax returns. How would it look?”

Romney denied this, saying Reid needs to reveal his source.

“Harry Reid really has to put up or shut up,” Romney said.

The book Double Down: Game Change 2012 cited Jon Huntsman Sr., whose son Jon Huntsman Jr. ran for president in 2012, as the source of the tax rumor, an accusation Huntsman denied.